1. Field of the Invention
The present invention relates to an image projector and a display device, and more particularly to a method and a device for adjusting the color of an image when the image is projected to the outside through an image projector.
2. Description of the Related Art
A device having the function of projecting an image can project the image in a direction and place specified by a user. The image projecting device, typically, displays image data stored in a memory or image signals input through an image input terminal on a screen. The place on which an image can be displayed in such a manner may be anything desired by the user. For example, an image is formed may be formed on white wall or a plane with an arbitrary color that is used as a screen.
Generally, the device provided with the image projecting function has an object to reproduce and project color information of each pixel constituting an image to be displayed as it is. For example, assuming that the image is to be displayed using RGB color information, and the color of a specific pixel is [255,0,0], the image projecting device displays a color corresponding to the color [255,0,0] as it is at the position of the pixel. This is a basic function of a display device, and a general image projector is also manufactured to follow such a function.
However, in a case of an internal display device such as a Liquid Crystal Display (LCD), the screen on which an image is formed is a part of the internal display device, and such a screen is manufactured to express the image clearly when it is generally manufactured. However, the image projector does not include a screen on which an image is generally displayed as a part of the device. In this case, the image projected by the image projector is changed depending on a working environment. For example, if the color of a screen on which an image is displayed is a green [0,255,0] system when it is assumed that an image of red [255,0,0] is displayed using the image projector, the red image does not appear red but yellow [255,255,0]. That is, the image may be shown in another color because of the influence of the color of the screen. Further, the color of a displayed image may be shown to be changed, or the distinction of the color may be shown to be different depending on a surrounding light source.
As such, the image projector generally projects an image to the outside of a corresponding device, and has a characteristic different from the internal display device, such as an LCD. The internal display device can facilitate required settings, and effectively display the color of an image using the values of the settings. However, in an external display device, such as the image projector, the color of an image is greatly influenced by environments where the image is projected, e.g., the brightness of an external light source, the color of a screen and the like. Such projection environments generally have a negative influence on the quality of a projected image. If an image is projected in the same manner as in the internal display device without processing of the projection environments, the quality of the projected image is lowered.